Photographic transfer materials bearing gelating anion soap complex silver halide layer



1950 .1. A. H. HART 2,527,253

PHOTOGRAPHIC TRANSFER MATERIALS BEARING GELATIN ANION SOAP COMPLEX SILVER HALIDE LAYER Filed Nov. 15, 1946 SILVER HAL/DE DISPERSED IN GELAT/N- 3 ANION SOAP COMPLEX METAL SHEET 4 LAGOUER 5 VER HAL/DE maps/e550 //v GEL/ITIN- 3' gsmwm xxammm wammmmm AlV/O/V SOAP GOMPL E X AND GOLLOU/ON PA PE I? Fig. 2

INVENTOR.

JOHN ALFRED HENRY HART M-W W A TTORNE i atentecl Oct. 24, 1950 UNITED STATES. PATENT f OFFICE 2,527,263, r PHOTOGRAPHIC TRANSFER'MATERIAES BEARING GELA-TIN ANION SOAP COM PLEX SILVER HALIDE LAY-ER' j t J ohnAlfred Henry Hart, Ilfo r d, England, as sig'nor t lllford Limited, Ilford, .Iilng'land, a British company Application November 15, 1946,,Se11ialN0. 110,231

In Great Britain N ovember 19,1 945 4 Claims.

This invention relates to photographic materials and particularly to transfer materials from which a photographic light-sensitive emulsion layer may be transferred to another support.

Processes have been described for the production of templates and other manufactured articles wherein a photograph is formed on a supportwhich is subsequently to be cut to the shape dictated by the photographic image. The supports areusually of metal, wood or a synthetic plastic. I

Photographic materials in. which the emulsion layer is carried on'a temporary support and from which the emulsion layermay be transferred to a permanent support are well known. It is possible to form the latent image. in the'emulsion, process it whilestill on the temporary support. andlthen transfer the processed. image to the permanent support, butin many. instances, espe cially where dimensional accuracy is important, itis preferable to transfer the emulsion layerto the permanent support before it is processed and to carry out the processing. while it is. on. the. permanent support since'thedimensions of v the permanent support are usually stable.

Unfortunately, ordinary gelatin photographic emulsions do not adhere very well to metal sup-j ports. It has therefore. been proposed to pro-. vide the permanent metal support, and. also the emulsion. layer,v with an over-coating of a lacquer, usually a; nitrocellulose lacquer, and

then to secure adhesion by softening the lacquer layers, pressing them together, allowing the assembly to dry, and then'stripping off the temporary support (which is usually paper). Another method is tofsoften thela'cqu'er coatings byheating.

This. method requiresithat the" manufacturer of the transfer'material provides an outercoat+ ing of lacquer on the" emulsion.

The present invention is concerned with an improved transfer material which avoids the necessity for a lacquer'coat over the emulsion.

According to this invention a transfer mate- By the expression dry-stripping layer is.

meant a layer which maybe broken down by.

of maleic. acid or anhydride pulling apart layers either side entry manual force at ordinary" temperatures and Without the application of any name;

The production of photographic emulsions of the type just defined is described in U. S. application No. 623,445, filed October 19, 1945, to

reiererrce j may be made for the" fun de tails. Briefiythe method consists in forming an emulsion of silver halidei'ri an aqueous solution of gelatin, adding to such emulsion an anion soap or a sulphonic acid having a highly hydrophobi'c'rad'icl'e" in the anion in suffi'cient quantity to causeprecipitation of a complex of the gelatin and the added substance, the said complex containing'"tli'edispersd silverli-alide", and thenre dispefsing' ,th"e complex in' a: predominantly or-' garlic sonenrmedinm; Preferably the anion soap or sulphoni'c'a cid' is added to the gelatin at a pH belowtheisoelectric pointo'f' the gelatin" or" in the presence of an electrolyte. There maybe included inaphotographidemulsion so formed a proportlon df another colloid which is soluble in the organic solv'efit 'rnediuinfoi"which is s0lu"-' tile] in a solvent medium which is miscible with" the solvntmedium already present to form a stable dispersion. x Such'other' colloids maybe;- for 'exampigicniuicse" esters; e: gi, ceuuiose" nitrate, celluloseac'e'tate, far-hydrolysed cellulose esters (e. .g.,.cellulose acetate" having? an acetyl ccntentpf 20:3( polyvinyl acetate, polyvinyl acetals, methyl ihethacrylate polymers and the partial hydrolysis products thereof; and mixed'interpoiyinerssucn as the interpol mers with styrene or metnyl'inetnacrylate; r

Suitable anionsoaps'and sulphonic acids containingi' nigniy hydrophobic radie'les inf the anions" are listed in application No; 623, 44'5; They include: (a Soluble salts of long-chain-alkyl sulphonic acids.

(b) Solublesaltsf' of 'sulphated higher fatty a l; cohols, e: g, plliblesalts of fattyalcohol' sulphates of which the alkyl group" contains at least s'carbon'atoms; as'for example the sdlubleSalts of iauryihydrogen"suipuateand oleyl hydrogen sulp ate: h (c) Soluble salts ofsulphated secondaryalc'm holscontaifiing 'at"least8" carbon atoms in the chain"; v

(d) Soluble salts' of' alkylated aromatic sulphonic acids, ei'gt, s'oluble'saltspf alkyl benzene" sulphonic acids, of alkyl naphthalene sulphonic acids" and of' alkyla'ted hydroxy diphenyl sulZ-y phonic ac'idsi' phonic acid which contains a carbonamide' The expression long-chain-alkyl" is intended to mean at least 8, and preferably at least 12, carbon atoms in the alkyl group. I

Very many anion soaps are commercially marketed as detergents and these commercial products may conveniently be employed in the process of this invention. Thus, suitable commercial products are the compounds sold under the trade names:

Agral N The sodium salt of alkyl naphthalene sulphonic acid.

Aresklene 375 The sodium salt of alkyloxydiphenyl disulphonic acid.

Dispersol L The sodium salt of dinaphthyl-methane disulphonic acid.

Gardinol Sodium alkyl sulphate.

Igepon T The sodium salt of oleoylmethyl amino-ethane su1-' "phonic acid.

32:33} 2 Sodium 'h'exa'dec'yl sulphate.

Lissatan A Sodium, hexadecyl sulphate and formaldehyde.

Lohrinol Sulphonated, fatty acid.

Nekal A The .sodiuin' salt of alkyl Nekal BX naphthalene sulphonic ac- Perminal W id.

Santomerse D The sodium salt of alkyl ben I zene sulphonicacid. Sulphonated Lorol TA Trieth'anolamine dodecyl 3111- There may be used, instead of the anion soap itself, the free acid derived from such soap.

As indicated above, instead of true anion soaps, sulphonic acids of which the anion is highly-by drophobic maybe employed..These may be simple acids, for example 2-naphthol-1-sulphonic acid, l-naphtholl-sulphonic acid or anthraquinone- 2-sulphonic acid, or maybe more complex, for

example dyestuffs such as Kiton Fast Yellow 3G (Colour Index No. 645) which contains a sulphoaryl-pyrazolone radicle, and Naphthalene Orange GS (Imperial Chemical .Industries Ltd.) By Colour Index is meantv Society, ofv Dyers and Colourists Colour Indexfi edited, by Rowe,

D. Sc., F. I. C., first edition, January,,l 924, pub-.

lished by The Society at the General Ofiices, 30

Pearl Assurance Buildings, Bradford, Yorkshire. In general it is preferred to form the complex from an aqueous gelatino-silver halide emulsion which has already been washed and digested.

Generally speaking the most suitable organic solvents for dispersing the complexes are those containing hydroxy groups, e. g. methyl and ethyl alcohols, ethylene glycol mono methyl ether, ethyl lactate and diacetone alcohol. Organic solventsnot containing hydroxy groups are generally only useful together with some water or some hydroxy solvent, e. g. acetone, methyl ethyl ketone, dioxane, methylene chloride, chloroform and mesityl oxide are preferably used in admixture with water or methyl alcohol. Small quantitles of esters, e. g. methyl acetate, butyl acetate, ethers, e. g. diethyl ether, and hydrocarbons, e. g. benzene and toluene, may also be included in the solvent medium. The choice of solvent will depend on the particular nature of the complex. Complexes formed at low pH and containing a relatively low proportion of the anion soap (or corresponding acid) are generally more easily soluble in polar solvents'or in solvents containing some water, whilst those formed at higher pH values and containing more anion soap (or corresponding acid) are generally soluble in nonpolar solvents, e. g. toluene. The complexes may be swollen in the organic solvent medium and dispersion is usually facilitated by gentle warm- Any of the specific-emulsions described in the aforesaid application No. 623,445 may be employed in the present invention.

transferred to metal (e. g. steel,"aluminium, brass,-

copper or nickel), Wood, plastic or other surfaces as required. Generally it is desirable that the surface to which the emulsion is'to be transferred should have a lacquer surface, e. g. cellulose nitrate, cellulose acetate, polymethyl methacrylate or polyvinyl acetate. Where the surface to which the emulsionis'tobe transferred consists of such a plastic, softening of'the actual surface of the material by the application of a solvent or by heat is usually suflicient to secure adhesion, no separate application of a lacquer layer being necessary. Y I

i The following examples illustrate the produc tion and use of transfer material according to this invention:

of water and melted down. To. this was added 125 cc. of normal hydrochloric. acid. and 17.5 cc. of.

Teepol X (a commercialjanion soap'com-prisingf.

a mixture of sodiumalkyl sulphates). A complex of the gelatin and the anion soap, holding the sil-. ver iodobromide in suspension, was precipitated, and this was washedv with 2,-lit'resof .water, drained, dissolved in 500 cc. of warm ethyl alcohol (64 0. P.) and then re-precipitat'ed byadding 3'75 cc. of distilled water. i The precipitate was then drained and dissolveddn 1 litres of warm ethyl alcohol (64 0. P.)..

A paper base was coated with 21.5% solutionof beeswax in trichlorethylene and dried. It was then coated withthe emulsion preparedas above and again dried. The resulting photographic transfer material, is shown in section in Fig. 1

of the drawing whereinpaper Lhas beeswax layer 2 coated on one surface which carries the amazes fix light-sensitivelayer 3 of silver halides dispersed the e a in a o o p. omp ex- 4 A sheet of metal was lacqueredfwith a cellulose nitrate lacquer. and allowed .to dry. The lacquer layer was softened by the application of a solvent mixture consisting of equal volumes of methyl alcohol and ethylene glycol monomethyl. ether applied. with a swansdownpad; Thetransfer material was then applied to.the; metal sheet with the emulsion side in contact with the softened lacquer surface, the assembly pressed and allowed to dry-Rout. for one hour. The paper basewas then stripped away, leaving the emulsion adhering fi'rhilytothe metal sheet.

Example 2 i "1 400 gms. of a silver iodobromide emulsion containing 40 gms. gelatin was melted at 110 F. and mixed with 20 gms. of diatomaceous earth ground 111.200 and 2% gelatin solution. To this was added50 of normal hydrochloric acid and 70 .cc.::,of,'I eepol X. The resulting precipitate was separated, washed with water, drained and added to 200 cc. methyl alcohol. The temperature was raised to 125 F. and the mixture stirred until, the precipitate had all dissolved. To the product was added 150 cc. distilled water and the resulting precipitate thoroughly drained. The precipitate was then dissolved in 300 cc. of ethylene glycol monomethyl ether and to this was added 30 gms. of collodion cotton HM 15/20, manufactured by Imperial Chemical Industries Limited, made into a slurry with 300 cc. butyl alcohol and 60 cc. of diacetin. The mixture was stirred for 40 minutes at 125 F. and then allowed to cool. It set to a jelly.

This stock jelly was used to make up an emulsion for coating by melting 250 gms. of the jelly at 125 F. and adding it to 750 cc. of methyl alcohol at 1lO-1l5 F. This was allowed to cool, making about 1 litre of emulsion suitable for coating.

This emulsion was coated on a beeswaxed paper support as in Example 1 and yielded a transfer material of similar Value for transferring an emulsion to a lacquered metal support. The resulting transfer material is shown in Fig. 2 of the drawing adjacent to a metal sheet 4 bearing lacquer layer 5. The sheet and transfer material are shown in section and the former consists of paper support I bearing beeswax layer 2 which carries light-sensitive layer 3 composed of silver halides dispersed in a mixture of the complex of gelatin and the anion soap with collodion cotton.

Example 3 A zinc sheet was coated with the thermoplastic lacquer:

Polyvinyl acetate (Gelvo 1%) gm 40 Tri-cresyl phosphate cc 5 Ethyl acetate cc 100 Butyl acetate cc 50 When dry and non-tacky, the emulsion coated paper of Example 2 was pressed into contact with it (emulsion side to lacquer surface) by an iron heated to above 110 C. for about seconds. Immediately the iron was removed, the assembly was rolled with a rubber roller to squeeze out air bubbles and, after cooling, the paper support was stripped away, leaving the emulsion attached to the metal sheet. Adhesion was good during processing and when dried.

When all smell of solvents had disappeared, the paper of Example 2 was squeegeed on to the tacky surface, and the backing paper stripped away, leaving the emulsion adhering to the metalsheet'; Adhesion was good during processing and when dry. During processing most of the triacetin was leached out, and the; lacquer lost its tackiness, becoming hard. It has been found that lacquered metal sheets to which emulsion layers have been transferred in accordance with this invention, have good keeping qualities. The emulsion does not tend to separate from the metal either during the photographic processing or when the layer is dried after processing. There is little or no tendency for the emulsion to creep on the metal, a phenomenon sometimes observed with other methods of making sensitised metal sheets. A further and very important advantage of the use of transfer material in accordance with this invention is that the emulsions cut more smoothly than normal gelatin emulsions with less tendency to-chip or tear around the line of the cut, a matter of considerableimportance in the manufacture of templates.

While this invention primarily consists in the novel transfer material hereinbefore described, it also includes the method of sensitising sheets of metal, wood, plastic or other material hereinbefore described and the method of making templates and similar articles wherein a latent image in an emulsion transferred to a metal or other support as described, is processed, and the metal is cut to a form dictated by the resulting photographic image.

What I claim is:

l. A photographic transfer material adapted for lamination of the emulsion layer directly to the lacquered surface of a template comprising the following layers in order: a temporary support layer, an adhesive dry stripping layer and a layer of a photographic emulsion said latter layer being composed of light-sensitive silver halides dispersed in an ionic complex formed between gelatin and a compound selected from the group consisting of anion soaps and sulphonic acids containing a highly hydrophobic radical in the anion, said complex being the essential binding agent for the silver halide-grains and being soluble in a solution composed of methyl alcohol.

2. A photographic transfer material adapted for lamination of the emulsion layer directly to the lacquered surface of a-template comprising the following layers in order: a paper support layer, an adhesive dry stripping layer and a layer of a photographic emulsion said latter layer being composed of light-sensitive silver halides dispersed in an ionic complex formed between gelatin and a compound selected from the group consisting of anion soaps and sulphonic acids containing a highly hydrophobic radical in the anion, said complex being the essential binding agent for the silver halide grains and being soluble in a solution composed of methyl alcohol.

3. A photographic transfer material adapted for lamination of the emulsion layer directly to the lacquered surface of a template comprising the following layers in order: a paper support layer, an adhesive dry stripping layer and a layer of a photographic emulsion said latter layer being composed of light-sensitive silver halides dispersed in anionic complex formed between gelatin and-a compound selected from the group consisting of anion soaps and sulphonic acids containing a highly hydrophobic radical in the anion, said complex being the essential binding agent for the silver halide grains and being soluble in a solution composed of methyl alcohol, and

containing a proportion of an organic solventsoluble colloid of a different type from said complex.

4. A photographic transfer material adapted for lamination of the emulsion layer directly to the lacquered surface of a template comprising the following layers in order: a paper support layer, an adhesive dry stripping layer and a layer of a photographic emulsion said latter layer being composed of light-sensitive silver halides dispersed in an ionic complex formed between gelatin and a compound selected from the group consisting of anion soaps and sulphonic acids containing a highly hydrophobic radical in the anion, said complex being the essential binding agent for the silver halide grains and being soluble in a solution composed of methyl alcohol, and containing a proportion of an organic solvent soluble cellulose derivative.

JOHN ALFRED HENRY HART.

REFERENCES CITED L UNITED STATES PATENTS in the Number Name Date 2,118,059 Slack et a1". 1 .1 May 24,- 1938 2,142,311 Heidenhain Jan. 3,- 1939 12,275,727 Carroll et a1 Mar. 10, 1942 2,282,001 Russell et a1 May 5, 1942 2,326,058 Nadeau Aug. 3, 1943 2,362,593 Staehle Nov. 14, 1944 2,386,602 Giosefii Oct. 9, 1945 2,409,564 Heinecke et a1 Oct. 15, 1946 2,415,442 Rackett Feb. 11, 1947 2,489,341 Waller et al Nov. 29, 1949 FOREIGN PATENTS Number Country Date 7 537,256 Great Britain Oct. 12, 1940 554,300 Great Britain June 28, 1943 554,301 Great Britain June 28, 1943 556,360 Great Britain Oct. 1, 1943 OTHER REFERENCES Journal of the American Chemical Society, December 1943, pages 2187-2190; May, 1944, pages 692697. 

1. A PHOTOGRAPHIC TRANSFER MATERIAL ADAPTED FOR LAMINATION OF THE EMULSION LAYER DIRECTLY TO THE LACQUERED SURFACE OF A TEMPLATE COMPRISING THE FOLLOWING LAYERS IN ORDER: A TEMPORARY SUPPORT LAYER, AN ADHESIVE DRY STRIPPING LAYER AND A LAYER OF A PHOTOGRAPHIC EMULSION SAID LATTER LAYER BEING COMPOSED OF LIGHT-SENSITIVE SILVER HALIDES DISPERSED IN AN IONIC COMPLEX FORMED BETWEEN GELATIN AND A COMPOUND SELECTED FROM THE GROUP CONSISTING OF ANION SOAPS AND SULPHONIC ACIDS CONTAINING A HIGHLY HYDROPHOBIC RADICAL IN THE ANION, SAID COMPLEX BEING THE ESSENTIAL BINDING AGENT FOR THE SILVER HALIDE GRAINS AND BEING SOLUBLE IN A SOLUTION COMPOSED OF METHYL ALCOHOL. 